Motorola ASTRO 25 GTR 8000 - UHF Duplexer Isolation Verification Set up; Figure 77: Verifying UHF Duplexer Isolation - Connecting Test Equipment; Verifying UHF Duplexer Insertion Loss

5.10.5.6.1
Verifying UHF Duplexer Insertion Loss
Procedure:
1 Connect test equipment as shown in Figure 75: Verifying UHF Duplexer Insertion Loss —
Connecting Test Equipment
on page 181.
2 Observe and note the level in dBm as shown on the millivoltmeter.
3 Connect the duplexer cable assembly and test equipment to the duplexer as shown in Figure 76:
Verify UHF Duplexer Insertion Loss — Connecting Duplexer Cable Assembly on page 181.
4 Observe and note the level in dBm as shown on the millivoltmeter.
5 Subtract the absolute number noted in step 2 from the number noted in step 4. The difference
should be less than 1.3 dB to meet specification for Insertion Loss.
6 Repeat steps 1 through 5 for Low-Pass/High-Notch cavities with the following exceptions:
a Set service monitor to Rx or Tx frequency, whichever is lower.
b Connect millivoltmeter to Low Pass duplexer input (cavity #1).
c Connect terminator to cavity #6.
5.10.5.7
UHF Duplexer Isolation Verification Set Up
Figure 77: Verifying UHF Duplexer Isolation — Connecting Test Equipment
MN003286A01-E
Chapter 5: GTR 8000 Base Radio Optimization
182